Israel has about 15M population, with around half of them being Palestinians. Out of that, only about 1.7M have Israeli citizenship, and can vote. The rest around 5.5M who live in Gaza/West Bank cannot.
Although Palestinians living in Israel can vote, there has been a long history of political suppression of Palestinian voices and parties, and also discriminatory laws and systemic oppression, which ensure that Palestinians dont have the same rights. In reality, they have very little to no influence on policy.
Palestinians living under occupation in the the West Bank and Gaza cant even participate in elections.
https://reliefweb.int/report/occupied-palestinian-territory/not-vibrant-democracy-apartheid